Loot Table Simulator
Design weighted drop tables and verify them with Monte Carlo simulation before they ship. Measure real rarity distributions, worst-case droughts and pity behaviour — then export to Godot or Unity.
Table workspace
Edit the table on the left, verify the measured distribution on the right
Table
Total weight 1000
Pity / guarantee
Simulation
Drop entries (6)
| Item | Rarity | Weight | Min | Max | Per open | Remove |
|---|---|---|---|---|---|---|
| 50.00% | ||||||
| 30.00% | ||||||
| 12.00% | ||||||
| 6.00% | ||||||
| 1.80% | ||||||
| 0.20% |
No simulation run yet
Set an open count and press Simulate. Results appear here with expected vs observed rates and worst-case droughts.
100,000 opens · seed "jaconir"
Loot analysis
Validate the economy before you export the table
Run a simulation to analyse the economy
Expected vs observed charts stay in the workspace — the report, warnings, and EV breakdown appear here.
Designer presets
Dungeon · boss · treasure · quest · enemy · crafting · daily
Professional tips
Only what changes the table you ship
Probability
Run at least 100 ÷ rarest rate. Read expected vs observed — large deviation on rares usually means too few opens, not a broken table.
Player Psychology
Longest dry streak is the quit moment. Pity turns an unbounded worst case into a known cost players can commit to.
Economy Balance
Separate currency from gear when possible. If gold dominates chest EV, every “drop” feels like a failed roll and inflation creeps in.
Reward Frequency
Multiple rolls compound: 10% × 4 rolls ≈ 34% per open. Use Expected Value Breakdown to see what players actually earn per session.
Continue your game dev workflow
Idea → level → art → collision → audio → progression
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Frequently asked questions
How many opens should I simulate?
At least 100 ÷ your rarest probability. Default 100,000 resolves rates near 0.01%. Check Simulation Confidence in the analysis report.
Weighted vs independent mode?
Weighted picks one entry per roll by weight (chests, bosses). Independent gives each entry its own chance (common enemies with empties).
What is Economy Health?
A ship-readiness score from legendary rate, variance, and observed vs theoretical value. Watch or Unbalanced means fix warnings before export.
How does pity work?
After N opens without the target rarity, the next open forces it and resets. Natural hits also reset. Exported Godot/Unity code includes the same logic.
Are results reproducible?
Yes — seeded mulberry32. Same seed, table, and open count always match.
Is anything uploaded?
No. Simulation runs in your browser only.